Adjustable harrow



(No Model.) J. L. LAUGHLIN.

ADJUSTABLE :HARROW.

- PatentgdMa-r, 20, 1883.

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. UNITED. STATES PATENT OFFICE.

. JOHN L. LAUGHLIN, OF RAGINE, WISCONSIN.

ADJUSTABLE HARROWp SPECIFICATION forming part of Letters Patent No. 274,125, dated March 20, 1883.

Application filed August 1, 1882. (No model.) I

To all whom it may concern:

Be it known that I, JOHN L. LAUGHLIN, a citizen of the United States, residing at Racine, in the county of Racine and State of Wisconsin, have invented certain new and V useful Improvements in Adjustable Harrows, of which the following is a specification.

This invention relates to that class of harrows in which means are provided for adjusting the teeth so as to set them at any desired angle.

My improvement consists in the features of construction and combination hereinafter described, ahd illustrated in the accompanying drawings, in which-- Figure l is a top or ground view of the harrow; Fig. 2, an end view as it appears with opposite to admit of their being attached to the bar A with one bolt or rivet, E. The inner faces of the portion extending above the bar A are at right angles to it and the proper distance apart to receive the parallel bars 0 G, to which r they are pivoted by means of bolts or rivets D D,in which manner the toothbars A are connected to the parallel crossbars 0 0 throughout. Attached to the parallel bars 0 (J is a lever, G,arranged to lock, by means of a spring-pawl or other suitable device, to a quadrant, F, secured to the upper bar, 0, which lever G, driving the parallel bars 0 O in opposite directions simultaneously, im-

parts a' reciprocating oscillating motion to the tooth-bars A A, thereby enabling the teeth to be inclined to clear them of trash, or set and held at any angle.

Heretoi'ore various means have been devised for adjusting the teeth, and the operating-1evers for oscillating the tooth-bars have been connected to the harrow in a variety of ways; but it will be observed that I employ above the tooth-bar two sets of bars which are pivotally connected together by links, and also at their lower ends pivoted to. thetooth-bars; also, that the lever is pivoted to one bar of each upper set, and that the links of each pair have their upperopposiug faces in planes at right angles to the axisof the tooth-bar. Ar ranging the links thus in pairs not only gives strength to the barrow, but prevents disarrangement of any of the parts by reason of the strain incurred. The tooth-bars, being below the upper sets of connected bars, have all necessary swing, and, in fact, the whole structure is greatly simplified.

l I claim- The combination, in an adjustable barrow, of the tooth-bars A, with the links B secured in pairs to the tooth-bars, on op-positesides thereof, and pivoted to the bars 0 of the two upper sets of bars which lie in different planes and are located transversely to the tootlpbars, and the lever G, provided with a latchingdevice and pivoted to one bar of each upper set, each pair of links which embraces one bar of each set having their opposing faces in planes at right angles to the tooth-bars, substantially as described.

JOHN L. LAUGHLIN.

Witnesses v H. G. STAVER,

SIMEON VVHITELEY. 

